Background. The existing literature highlights a lack of comparative studies between subtypes of cholangiocarcinoma (CC) and the impact of misclassification on the epidemiological parameters. Methods. A retrospective study was conducted to evaluate the surgical outcomes. The authors used Poisson regression with modified errors to calculate the risk ratios (RR) and reported post-estimation marginal effects. Coefficient estimates, variance inflation factors, and Pearson’s goodness-of-fit test statistics were used to check for multicollinearity and model fit, respectively. We also performed a reclassification analysis by modeling Klatskin tumors (PCC) as extrahepatic (ECC), reclassifying them as intrahepatic (ICC), and comparing the corresponding changes in estimates. Results. Regression analysis revealed an increased risk of death in patients with ICC (RR = 2.05, 95% CI 1.11–3.78) and PCC (RR = 2.03, 95% CI 0.97–4.24) compared to those with DCC. When PCC was analyzed as an ECC, the ICC revealed an RR of 1.52 (95% CI 0.84–2.73). Further reclassification of PCC showed an RR of 2.04 for ICC (95% CI: 1.53–3.53). The adjusted marginal effects saw a reduction in the death probability for both ICC and ECC. However, post hoc analyses revealed insufficient evidence for differences between the reclassified models. Conclusions. Patients with DCC had slightly better prognosis compared to ICC and PCC. We found no differences in survival between ICC and ECC (combining DCC and PCC). The decrease in mortality risk due to reclassification in both groups was not confirmed statistically. Future studies should focus on statistical evidence when referring to the Will Rogers phenomenon, instead of inferring from raw comparisons.
背景：现有文献指出，目前缺乏对胆管癌（CC）亚型之间的比较研究，以及错误分类对流行病学参数影响的探讨。方法：本研究采用回顾性分析评估手术预后。作者使用修正误差的泊松回归计算风险比（RR），并报告了估计后的边际效应。通过系数估计值、方差膨胀因子和皮尔逊拟合优度检验统计量分别检验多重共线性和模型拟合度。我们还通过将Klatskin肿瘤（PCC）建模为肝外胆管癌（ECC）、重新分类为肝内胆管癌（ICC），并比较相应估计值的变化，进行了重分类分析。结果：回归分析显示，与远端胆管癌（DCC）患者相比，ICC（RR=2.05，95% CI 1.11–3.78）和PCC（RR=2.03，95% CI 0.97–4.24）患者的死亡风险增加。当PCC被分析为ECC时，ICC的RR为1.52（95% CI 0.84–2.73）。进一步重分类PCC后，ICC的RR为2.04（95% CI：1.53–3.53）。调整后的边际效应显示ICC和ECC的死亡概率均有所降低。然而，事后分析表明重分类模型之间的差异证据不足。结论：与ICC和PCC相比，DCC患者的预后略好。我们发现ICC与ECC（合并DCC和PCC）之间的生存率无差异。两组因重分类导致的死亡率风险降低均未得到统计学证实。未来研究在涉及威尔·罗杰斯现象时，应侧重于统计证据而非原始比较推断。
Understanding the Will Rogers Phenomenon in Cholangiocarcinoma Research and Beyond
肿瘤(癌症)患者之家